Riviera GamehelpBut anyway:
1. If you can learn something of an item you recieve, or it does a stupidly huge amount of damage, or, in rare cases, you need the effect the item gives ( Example being later on in the game when you have Bomber Kids who can potentially destroy the bridge unless you use Slumber Ivy ), keep it. If not, no.
2. You get certain item drops if you S rank, especially on Bosses. Also, as you said, more TP.
3. If you S rank enough, then yes, it is worth it, as you can get many conversations and items this way.
[13:27:43] [Sabator] peter would be the worst batman ever though. "turn on the bat-signal" "right!" *turns on huge foglight, beams an image of striped pantsu into the sky*